package platform

import (
	"strings"
)

// fmtMDTable renders a markdown table with column widths padded so the table
// is readable as plain text without a markdown renderer.
//
// headers contains the column header strings.
// rows contains data rows; each row must have the same number of cells as headers.
// Cells with fewer entries than headers are treated as empty.
func fmtMDTable(headers []string, rows [][]string) string {
	ncols := len(headers)
	if ncols == 0 {
		return ""
	}

	// Compute max width per column.
	widths := make([]int, ncols)
	for i, h := range headers {
		if len(h) > widths[i] {
			widths[i] = len(h)
		}
	}
	for _, row := range rows {
		for i := 0; i < ncols; i++ {
			cell := ""
			if i < len(row) {
				cell = row[i]
			}
			if len(cell) > widths[i] {
				widths[i] = len(cell)
			}
		}
	}

	var b strings.Builder

	// Header row.
	b.WriteByte('|')
	for i, h := range headers {
		b.WriteByte(' ')
		b.WriteString(h)
		b.WriteString(strings.Repeat(" ", widths[i]-len(h)))
		b.WriteString(" |")
	}
	b.WriteByte('\n')

	// Separator row.
	b.WriteByte('|')
	for i := range headers {
		b.WriteString(strings.Repeat("-", widths[i]+2))
		b.WriteByte('|')
	}
	b.WriteByte('\n')

	// Data rows.
	for _, row := range rows {
		b.WriteByte('|')
		for i := 0; i < ncols; i++ {
			cell := ""
			if i < len(row) {
				cell = row[i]
			}
			b.WriteByte(' ')
			b.WriteString(cell)
			b.WriteString(strings.Repeat(" ", widths[i]-len(cell)))
			b.WriteString(" |")
		}
		b.WriteByte('\n')
	}

	return b.String()
}